"The burned-over district" is fascinating. Within a fairly small portion of space and time (upstate NY, mid-19th century) originated a panoply of religious and social innovation: Mormonism, the Millerite millenialist sect and its offspring; Jehovah's Witnesses and Seventh Day Adventists, Spiritualism, the Publick Universal Friend, the women's suffrage movement, and more. Also, The Great Agnostic, Robert Green Ingersoll, came from roughly the same time and place.

I'm composing this separately before clicking over to the comments part...

My guess is that's Joseph Smith showing the Golden Plates to people who would later sign a statement that they saw them. Or something similar. I recall hearing that there were signed statements from a few people that they were shown the plates, although I've also heard why their attestations are dubious.